Discourse on the Method of Rightly Conducting the Reason, and Seeking Truth in the Sciences

DISCOURSE ON THE METHOD OF RIGHTLY CONDUCTING THE REASON,

AND SEEKING TRUTH IN THE SCIENCES

by Rene Descartes

PREFATORY NOTE BY THE AUTHOR

If this Discourse appear too long to be read at once, it may be divided

into six Parts: and, in the first, will be found various considerations

touching the Sciences; in the second, the principal rules of the Method

which the Author has discovered, in the third, certain of the rules of

Morals which he has deduced from this Method; in the fourth, the

reasonings by which he establishes the existence of God and of the Human

Soul, which are the foundations of his Metaphysic; in the fifth, the order

of the Physical questions which he has investigated, and, in particular,

the explication of the motion of the heart and of some other difficulties

pertaining to Medicine, as also the difference between the soul of man and

that of the brutes; and, in the last, what the Author believes to be

required in order to greater advancement in the investigation of Nature

than has yet been made, with the reasons that have induced him to write.

PART 1

Good sense is, of all things among men, the most equally distributed; for

every one thinks himself so abundantly provided with it, that those even

who are the most difficult to satisfy in everything else, do not usually

desire a larger measure of this quality than they already possess. And in

this it is not likely that all are mistaken the conviction is rather to be

held as testifying that the power of judging aright and of distinguishing

truth from error, which is properly what is called good sense or reason,

is by nature equal in all men; and that the diversity of our opinions,

consequently, does not arise from some being endowed with a larger share

of reason than others, but solely from this, that we conduct our thoughts

along different ways, and do not fix our attention on the same objects.

For to be possessed of a vigorous mind is not enough; the prime requisite

is rightly to apply it. The greatest minds, as they are capable of the

highest excellences, are open likewise to the greatest aberrations; and

those who travel very slowly may yet make far greater progress, provided

they keep always to the straight road, than those who, while they run,

forsake it.

For myself, I have never fancied my mind to be in any respect more perfect

than those of the generality; on the contrary, I have often wished that I

were equal to some others in promptitude of thought, or in clearness and

distinctness of imagination, or in fullness and readiness of memory. And

besides these, I know of no other qualities that contribute to the

perfection of the mind; for as to the reason or sense, inasmuch as it is

that alone which constitutes us men, and distinguishes us from the brutes,

I am disposed to believe that it is to be found complete in each

individual; and on this point to adopt the common opinion of philosophers,

who say that the difference of greater and less holds only among the

accidents, and not among the forms or natures of individuals of the same

species.

I will not hesitate, however, to avow my belief that it has been my

singular good fortune to have very early in life fallen in with certain

tracks which have conducted me to considerations and maxims, of which I

have formed a method that gives me the means, as I think, of gradually

augmenting my knowledge, and of raising it by little and little to the

highest point which the mediocrity of my talents and the brief duration of

my life will permit me to reach. For I have already reaped from it such

fruits that, although I have been accustomed to think lowly enough of

myself, and although when I look with the eye of a philosopher at the

varied courses and pursuits of mankind at large, I find scarcely one which

does not appear in vain and useless, I nevertheless derive the highest

satisfaction from the progress I conceive myself to have already made in

the search after truth, and cannot help entertaining such expectations of

the future as to believe that if, among the occupations of men as men, there

is any one really excellent and important, it is that which I have chosen.

After all, it is possible I may be mistaken; and it is but a little

copper and glass, perhaps, that I take for gold and diamonds. I know how

very liable we are to delusion in what relates to ourselves, and also how

much the judgments of our friends are to be suspected when given in our